package com.sky.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.sky.constant.MessageConstant;
import com.sky.entity.User;
import com.sky.exception.LoginFailedException;
import com.sky.mapper.UserMapper;
import com.sky.properties.WeChatProperties;
import com.sky.service.UserService;
import com.sky.utils.HttpClientUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;

@Service
public class UserServiceImpl implements UserService {
  // wx小程序登录接口地址
  public static final String WX_LOGIN_URL = "https://api.weixin.qq.com/sns/jscode2session";
  
  @Autowired
  private UserMapper userMapper;
  @Autowired
  private WeChatProperties weChatProperties;
  
  /**
   * 微信登录
   * @param code
   */
  @Override
  public User wxLogin(String code) {
    // 1.调用微信接口服务，获得当前微信用户openid
    String openid = getOpenId(code);
    
    // 2.判断openid是否为空，为空则抛出业务异常
    if (openid == null) {
      throw new LoginFailedException(MessageConstant.LOGIN_FAILED);
    }
    
    // 3.判断是否新用户
    User user = userMapper.findUserByOpenId(openid);
    
    // 4.是新用户，自动注册
    if(user == null) {
      user = User.builder()
          .openid(openid)
          .createTime(LocalDateTime.now())
          .build();
      userMapper.insert(user);
    }
    
    // 5.返回user对象
    return user;
  }
  
  
  /**
   * 当前微信用户openid
   * @param code
   */
  private String getOpenId(String code) {
    Map<String, String> params = new HashMap<>();
    params.put("appid", weChatProperties.getAppid());
    params.put("secret", weChatProperties.getSecret());
    params.put("js_code", code);
    params.put("grant_type", "authorization_code");
    String json = HttpClientUtil.doGet(WX_LOGIN_URL, params);
    JSONObject jsonObject = JSON.parseObject(json);
    String openid = jsonObject.getString("openid");
    return openid;
  }
}
